Is Rain Water Clean and Pure?

How many of us can remember drinking rainwater as kids? Now that you’ve grown up a bit, you’re probably wondering how safe it is to drink rainwater. Could you even use rainwater in place of your city drinking water supply?

Rainwater is clean and USUALLY safe to drink. You should only drink rainwater that has fallen directly from the sky, without touching plants or buildings. Test your rainwater’s PFAS levels before you use it for drinking water.

We’ve answered everything you need to know about the safety of drinking rainwater in this quick guide.

🚰 Can You Drink Rainwater?

The short answer is yes, you can usually drink rainwater – but not always. Rainwater is naturally distilled water that has been evaporated from the ground by the sun, then released back onto the earth from rain clouds.

Rainwater isn’t entirely pure – it usually contains ions such as calcium, magnesium, potassium, chloride, sodium, and bicarbonate, as well as nitrogen and other nitrogenous compounds.

However, rainwater is still typically*** cleaner than surface water and groundwater because it doesn’t pick up as many contaminants as on-ground and below-ground water sources.

Is that to say that rainwater is completely contaminant-free? No. In fact, there are several known contaminants in rainwater, which we’ll discuss later in this guide.

*** We say “typically” because we’re generalizing, here – rainwater may contain high levels of contaminants like PFAS, which make it unsafe to drink.

Continue Reading: The Hydrologic Cycle Explained

🚱 When Shouldn’t You Drink Rain Water?

There are a few occasions when you shouldn’t drink rain water.

📌 First of all, don’t drink rainwater that hasn’t fallen directly from the sky. For instance, if the rain hits plants or buildings before it reaches a clean container, the water will become contaminated by the surfaces it touches. You’ll need to treat the water accordingly to make it safe to drink.

For obvious reasons, don’t collect rainwater from puddles.

You also shouldn’t drink collected rainwater that has been stored in a dirty container. Most containers designed for rainwater collection are exposed to the elements and may become contaminated by dirt, insects, mold, bird droppings, animal contamination, or other particles from the air.

Finally, don’t drink rainwater in areas that are known to be polluted or from radioactive sites. Avoid collecting rainwater in regions near power plants, paper mills, chemical plants, or other sites of heavy industrial activity.

Related Article: Is it illegal to collect rainwater in the US?

🧫 Potential Contaminants in Rainwater

Some of the likely contaminants in rainwater are:

• PFAS – New research has emerged showing that PFAS – or forever chemicals – now exceed the safe level in rainwater deemed by the EPA. This study has changed the way that experts view rainwater, with many concluding that rainwater is unsafe to drink. PFAS may have reproductive effects and developmental effects, increase the risk of cancer, and interfere with hormone production.
• Heavy metals – When rain washes off roofs made from metals, including lead and copper, these metals may leach into the water. Lead is known to accumulate to dangerous levels in the body, leading to kidney and liver problems, reproductive issues, and cardiovascular effects. Asbestos, another common roofing material, may cause cancer.
• Dust, smoke, and airborne particles – Depending on where rain falls, it will pick up varying levels of smoke, dust, and other airborne particles. These particles may be harmless, or they may have serious health effects (such as chemical fumes in industrial regions).
• Bacteria and viruses – Pathogens like viruses and bacteria are most likely to get into rainwater due to the harvesting technique. For instance, if rain is collected in a barrel that’s not regularly sanitized and is exposed to the environment, bacteria are likely to build up inside the barrel, contaminating the water. Health effects of pathogens in rainwater include nausea, vomiting, diarrhea, and gastrointestinal upset, depending on the pathogen consumed.
• Nitrogen and nitrogenous compounds – Nitrogen is present in small amounts in rainwater across the world. Excessive nitrate intake may lead to birth defects, cancer, and other adverse health effects.

⚗️ How to Make Rainwater Safe to Drink

The best methods to make rainwater safe to drink are boiling and water filtration.

Boiling

Boiling your rainwater is an easy way to kill potential microbiological contaminants, like harmful bacteria and viruses, making your water safe for human consumption.

It’s a good idea to boil your rainwater if you think it might contain roof contaminants or pathogens from an unclean storage tank or rain barrel.

To boil your water, just add the water to a pot and place it on the stove. Bring the water to a rolling boil for at least three minutes. Let the water cool before storing in a clean, glass container for drinking.

Water Filtration

Boiling water kills microbes such as airborne bacteria, but it won’t remove physical particles that contaminate rainwater, like chemical contaminants, PFAS, dust particles, and nitrogen oxides. To do this, you need a water filter.

There are numerous types of water filters available today. The easiest way to filter rainwater is to add the water to a filtration pitcher, which will trap contaminants in a filter as water flows from a top chamber to a bottom chamber.

👉 Looking for great deals? Here are the Must-Buy Water Filter Pitchers for 2024!

It’s wise to test your rainwater with an at-home test kit to determine what it contains. That way, you can look for a water filter that removes these contaminants, giving you the best value for your money.

✅ How to Safely Store Rainwater

You’ll be able to enjoy the health benefits of drinking clean rainwater much faster if you store your rainwater safely.

Avoid storage solutions made from construction materials that are capable of contaminating rainwater, like plastics and metals.

💡 Ideally, use a container that has been disinfected before use. After collecting the rainwater, bring the container inside and transfer the water to a pot for boiling.

Store your boiled, cooled, rainwater in an airtight glass jar in the refrigerator.

❔ Is Rain Water Clean? FAQ

Is acid rain safe to drink?

Yes, drinking mildly acidic rain is considered safe and doesn’t have any known health effects. Keep in mind, however, that acidic water is more prone to metal leaching, so make sure you store your water safely in non-metallic containers.

Is rainwater cleaner than tap?

In some cases, rainwater is cleaner than tap water. City water is usually sourced from a surface water supply, and surface water picks up contaminants from the ground, including pesticides, nitrates, and heavy metals. City water is also disinfected with chemicals (usually chlorine). However, new research suggests that rainwater has higher-than-safe levels of PFAS, so it’s certainly not bottled water clean.

Is rain water cleaner than shower water?

Rainwater is usually cleaner than shower water, although it depends on where the pollution levels in your local area. You can safely shower in rainwater. Because rainwater is usually softer than normal shower water, it’ll be kinder to your skin and hair, too.

Is it healthy to drink rain water?

Rain water typically contains traces of minerals and ions, making it healthy to drink. However, rainwater is known to contain dangerous contaminants, too, like PFAS. The healthiness of rainwater depends on what the water contains and where it falls.

How do you know if rain water is clean?

The appearance and smell of rainwater should give you an indication of whether it’s clean or dirty. Clean rainwater should be completely clear, with no distinctive smell. Keep in mind that some harmful chemicals, metals, and other contaminants in rainwater are invisible, tasteless, and odorless.Testing your water is the best way to get a proper understanding of your water quality.